Ecology officials warn farmers about using unpermitted frost dams

According to the Washington State Department of Ecology, many frost ponds have been constructed in recent years without adherence to state laws and rules governing the safe design, construction and operation of these reservoirs.

These unpermitted dams are often improperly constructed and pose a risk to people and property, alike.

A frost pond is what some orchardists are using to keep the valuable fruit buds from freezing. A farmer will build a pond to store water and when temperatures reach freezing, they spray their trees with water, which encases the buds in ice.

According to Doug Johnson with Ecology's Dam Safety Office, this prevents the buds from freezing and is starting to replace smudge pots and fans.

Johnson said there is a high failure rate among unpermitted frost pond dams so the Department of Ecology will conduct an inventory of unpermitted reservoirs across Washington state.

The risks these dams pose is due to the fact most of them are on high ground. If the pond fails the water will run downhill and can ruin property or cause loss of life.

Johnson said in the last 15 years there have been five failures, and all five were unpermitted dams.

"There was no loss of life but there was quite a bit of crop damage," he added. "So far we've been lucky there hasn't been anyone hurt."

All frost ponds with more than 10 acre feet of storage needs to have a permit.

Before Ecology does its detailed inventory of these dams the Dam Safety Office is asking orchard owners and other property owners to voluntarily bring their dams into compliance with dam safety regulations.

For most situations, this means contracting Ecology to perform an initial inspection, then hiring an engineer to assess the dam in detail and recommending modifications necessary to bring the facility up to current safety standards.

Once a reservoir owner completes any required modifications and all other needed state permits are obtained, the dam will be in compliance. Owners failing to correct deficiencies could face fines up to $5,000 per day. Ecology can also order dangerous dams to be drained and removed.